In the industrial field, the original fault signals collected during the operation of the equipment have the characteristics of strong noise and multiple working conditions. Most of previous data-driven fault diagnosis methods for bearings have relatively weak anti-noise ability and generalization ability. To solve these problems, a novel bearing fault diagnosis method based on down-sampling in frequency domain and convolutional neural network (CNN), called Ds-CNN, is proposed. Down-sampling in frequency domain consists of maximum down-sampling with bias and noise transverse truncation, which can realize data augmentation, reduce the difference between samples in frequency domain, and reduce the influence of noise on signals in frequency domain. The CNN model based on frequency domain signals can automatically extract fault features from signals after down-sampling and complete the identification and classification of bearing faults. The results of the experiment show that Ds-CNN has higher recognition accuracy than common models under strong noise environment and multiple working conditions. 

Aiming at the problems in the current emergency management GIS systems integrated with atmospheric dispersion models, such as low spatio-temporal resolution and without 3D terrain, a set of three-dimensional gas diffusion simulation methods was proposed based on the CALPUFF model. The three-dimensional spatio-temporal distribution data of the gas diffusion concentration was obtained through multi-layer calculations, and the Marching Cubes visualization technology was used to read and display the data, achieving the dynamic gas diffusion effect in three-dimensional space. “12·23” Kaixian blowout accident was used as a case study and the simulation was carried out to compare with the actual situation in two and three dimensions. The results show that the three-dimensional calculation based on CALPUFF model has higher accuracy of the magnitude and spatial distribution of gas concentration, and the three dimensional spatio-temporal dynamic simulation has high resolution and reconstruction efficiency, achieving a good visual effect. It can better express the gas leakage process and diffusion pattern and provide an important auxiliary decision-making means for emergency management.

The objective of the study is to characterise the taxonomy of the thermophilic filamentous strain B121 isolated from the hot springs in Ganzi, Sichuan, and provide insight into its genetic basis for future application. The taxonomy of strain B121 was analyzed by using polyphasic approach encompassing genome analysis, phylogenetic analysis, secondary structure prediction, and overall analysis of morphology, sodium salt tolerance test combined nitrogen fixation ability. Phylogenetic analysis of 16S rRNA indicated that strain B121 closely clustered with strains Thermoleptolyngbya oregonensis PCC 8501, Thermoleptolyngbya albertanoae ETS-08 and Thermoleptolyngbya sp.O-77; the 16S-23S ITS secondary structure prediction showed that the D1-D1' region of strain B121 has certain similarity and high sequence identity with reference strains, but they have not reached the generalized threshold for the same species. Additionally, the secondary structures of V2, BoxB and V3 regions are quite different between B121 and other reference strains. Combined with the analysis of morphological investigation, strain B121 was identified as a new species of the genus Thermoleptolyngbya. In addition, the strain B121 can survive in NaCl and NaNO3 modified BG-11 medium with a concentration of 0.5 M, and it can also survive in NaCl modified BG-11 medium with a concentration of 1 M. When the gas phase condition is Ar:N₂:CO₂ = 79:20:1 (v:v:v), the acetylene reduction rate of strain B121 can reach 2564.1 nmol/(g·h). 

Aiming at the problem of LOD (level of detail) popping and aliasing when the LOD Level is switched, this paper proposes a shader-based smooth transition algorithm for LOD texture blending and antialiasing. According to the distance between the 3D model and the viewpoint, the opaque mask algorithm based on Alpha test and weighted adjacent frames antialiasing algorithm are used to generate transition materials between LODs to achieve smooth transition for LOD switching. It can not only improve the texture quality, but also ensure the fluency and authenticity of loading 3D scene. The experimental results show that, compared with the smoothing method of Unreal Engine 4, the average GPU time of the proposed algorithm is reduced by more than 8%, and the frame rate is increased by more than 8%. Compared with the existing texture smooth transition methods, this algorithm can optimize the GPU rendering performance, stabilize and improve the frame rate and maintain good visual effect, effectively solve the popping problem when the LOD Level is switched.

This paper studied the heat resistance of phycocyanin and the accumulation of phycocyanin under different light conditions in thermophilic cyanobacteria. With 30°C, 40°C, 50°C, 60°C, 65°C, 70°C, 80°C, 90°C as the experimental group, 25°C and 4°C as the control group, the placement time was set to 5 hours and 14 days. Alignments of both chain α and β were conducted to figure out the heat resistant mechanism. PKUAC-SCTE542 was cultured under different photoperiods and different combinations of light sources, and its growth and phycocyanin content were studied to explore the light conditions which were suitable for phycocyanin production. Shaking incubators with narrow band light at following wavelengths: white (400–800 nm), red (654 nm), green (511 nm), and blue (454 nm), photoperiods of 8L/16D, 12L/12D, and 16L/8D, were tested. Dry weight and content of extracted phycocyanin were measured. PKUAC-SCTE542 phycocyanin kept stable at 65°C environments, and still maintained 60% activity after being placed at 60°C for 14 days. Under the conditions of red light and photoperiod of 8L/16D, the yield of phycocyanin was the highest; while the productivity of phycocyanin was the highest when red light and photoperiod of 16L/8D were set. In result, PKUAC-SCTE542 showed great heat resistance ability in this research. With light screening done, the phycocyanin yield increased by nearly 100 mg/gDCW.